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What are the two main parts of a rhodopsin molecule?
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Photoreception
The mammalian eye has a cornea and a lens and functions as a dioptric system, in which light rays are refracted to focus on the retina.
A rhodopsin molecule consists of two primary components:
- Opsin: A colourless protein that forms the structural backbone of the molecule.21
- Chromophore: A small, light-sensitive pigmented molecule—typically retinal (the aldehyde of vitamin A)—that is attached to the opsin.21
When light is absorbed, the chromophore undergoes a change in configuration, which triggers the biochemical cascade necessary for vision.21